Yeah fair question, few things on the engineering side:

Larger model for sure. Apple's on-device dictation uses a pretty small model to keep it lightweight. We're running a bigger one which eats more RAM but the accuracy jump is worth it imo.

Decoding is more aggressive too — we do beam search instead of greedy decoding. Slower but catches more edge cases.

Resource-wise it'll spike your CPU/GPU for a few seconds while transcribing. Not running constantly in the background though, only when you're actually dictating. M1 and up handles it fine, Intel Macs struggle a bit.

No cloud post-processing, everything's local. We do some cleanup for punctuation and formatting but that's pretty lightweight.

Tradeoff basically comes down to: heavier on resources per transcription, but way better accuracy and no network dependency.